diff --git a/src/app-bundles/product-filter-bundle.js b/src/app-bundles/product-filter-bundle.js
index 41c2644..97be96c 100644
--- a/src/app-bundles/product-filter-bundle.js
+++ b/src/app-bundles/product-filter-bundle.js
@@ -12,6 +12,7 @@ const productFilterBundle = {
       dateFrom: new Date(),
       dateTo: new Date(),
       tags: [],
+      requiredTags: [], // Tags that products MUST have (AND logic)
       parameters: [],
     };
 
@@ -45,6 +46,10 @@ const productFilterBundle = {
     return state.productFilter.tags;
   },
 
+  selectProductFilterRequiredTags: (state) => {
+    return state.productFilter.requiredTags;
+  },
+
   selectProductFilterParameters: (state) => {
     return state.productFilter.parameters;
   },
@@ -56,6 +61,7 @@ const productFilterBundle = {
     'selectProductFilterDateFrom',
     'selectProductFilterDateTo',
     'selectProductFilterTags',
+    'selectProductFilterRequiredTags',
     'selectProductFilterParameters',
     (
       items,
@@ -64,8 +70,14 @@ const productFilterBundle = {
       dateFrom,
       dateTo,
       tags,
+      requiredTags,
       parameters
     ) => {
+      // Safety check - if items is not available yet, return empty array
+      if (!items || !Array.isArray(items)) {
+        return [];
+      }
+
       return items.filter((product) => {
         let pass = true;
 
@@ -96,7 +108,17 @@ const productFilterBundle = {
           }
         }
 
-        // apply tag filters
+        // apply required tag filters (must have ALL of these tags - AND logic)
+        if (pass && requiredTags.length > 0) {
+          for (var r = 0; r < requiredTags.length; r++) {
+            if (product.tags.indexOf(requiredTags[r]) === -1) {
+              pass = false;
+              break;
+            }
+          }
+        }
+
+        // apply tag filters (must have ANY of these tags - OR logic)
         if (pass && tags.length > 0) {
           let matchFound = false;
           for (var t = 0; t < product.tags.length; t++) {
@@ -174,6 +196,17 @@ const productFilterBundle = {
       });
     },
 
+  doProductFilterSetRequiredTags:
+    (requiredTags) =>
+    ({ dispatch }) => {
+      dispatch({
+        type: 'PRODUCT_FILTER_SET_VALUE',
+        payload: {
+          requiredTags,
+        },
+      });
+    },
+
   doProductFilterSetParameters:
     (parameters) =>
     ({ dispatch }) => {
diff --git a/src/app-pages/products/products.js b/src/app-pages/products/products.js
index 0c09f64..c7b8d10 100644
--- a/src/app-pages/products/products.js
+++ b/src/app-pages/products/products.js
@@ -30,11 +30,13 @@ export default connect(
   'selectProductDateRangeFrom',
   'selectProductDateRangeTo',
   'selectProductSelectSelected',
+  'selectProductFilterRequiredTags',
   'doModalOpen',
   'doProductFilterSetFilterString',
   'doProductFilterSetDateFrom',
   'doProductFilterSetDateTo',
   'doProductFilterSetApplyDateFilter',
+  'doProductFilterSetRequiredTags',
   ({
     authIsLoggedIn,
     productFilterResults: products,
@@ -43,12 +45,17 @@ export default connect(
     productDateRangeFrom: rangeFrom,
     productDateRangeTo: rangeTo,
     productSelectSelected: selectedProducts,
+    productFilterRequiredTags: requiredTags,
     doModalOpen,
     doProductFilterSetFilterString: setFilterString,
     doProductFilterSetDateFrom: setFilterDateFrom,
     doProductFilterSetDateTo: setFilterDateTo,
     doProductFilterSetApplyDateFilter: setApplyDateFilter,
+    doProductFilterSetRequiredTags: setRequiredTags,
   }) => {
+    // Tab state - 'primary' or 'all'
+    const [activeTab, setActiveTab] = useState('primary');
+
     // show / hide the filter panel
     const [filtersActive, setFiltersActive] = useState(false);
 
@@ -118,6 +125,31 @@ export default connect(
       doModalOpen(DownloadModal);
     }, [doModalOpen]);
 
+    // Handle tab switching and apply tag filter accordingly
+    const handleTabChange = useCallback((tab) => {
+      setActiveTab(tab);
+      const primarySourceTagId = '8a7f4e6b-3c2d-4a9f-b1e5-9d8c7a6f5e4d';
+
+      if (tab === 'primary') {
+        // Require "primary source" tag (exclusive filter)
+        if (!requiredTags.includes(primarySourceTagId)) {
+          setRequiredTags([...requiredTags, primarySourceTagId]);
+        }
+      } else {
+        // Remove "primary source" from required tags to show all sources
+        setRequiredTags(requiredTags.filter(tag => tag !== primarySourceTagId));
+      }
+    }, [setRequiredTags, requiredTags]);
+
+    // Apply the initial filter when component mounts
+    useEffect(() => {
+      const primarySourceTagId = '8a7f4e6b-3c2d-4a9f-b1e5-9d8c7a6f5e4d';
+      // Only initialize once
+      if (activeTab === 'primary' && requiredTags.length === 0) {
+        setRequiredTags([primarySourceTagId]);
+      }
+    }, [activeTab, requiredTags, setRequiredTags]);
+
     return (
       <>
         <div className='m-5 mb-5 inline-flex'>
@@ -346,6 +378,33 @@ export default connect(
           </div>
         ) : null}
 
+        
+                {/* Tab Navigation */}
+        <div className='border-b border-gray-200 mx-5 mt-5'>
+          <nav className='-mb-px flex space-x-8' aria-label='Tabs'>
+            <button
+              onClick={() => handleTabChange('primary')}
+              className={`${
+                activeTab === 'primary'
+                  ? 'border-indigo-500 text-indigo-600'
+                  : 'border-transparent text-gray-500 hover:text-gray-700 hover:border-gray-300'
+              } whitespace-nowrap py-4 px-1 border-b-2 font-medium text-sm`}
+            >
+              Primary Sources
+            </button>
+            <button
+              onClick={() => handleTabChange('all')}
+              className={`${
+                activeTab === 'all'
+                  ? 'border-indigo-500 text-indigo-600'
+                  : 'border-transparent text-gray-500 hover:text-gray-700 hover:border-gray-300'
+              } whitespace-nowrap py-4 px-1 border-b-2 font-medium text-sm`}
+            >
+              All Sources
+            </button>
+          </nav>
+        </div>
+
         <div className='flex-grow w-full mt-5 overflow-x-hidden max-h-full'>
           <div className='flex-1 min-w-0 flex'>
             {filtersActive ? (